Figure 3: EM of Toh-IR amacrine cells: Toh-IR profiles presynaptic to bipolar axons, ganglion cell dendrites and amacrine cell profiles
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a) Toh-IR processes are presynaptic to other Toh-IR processes (white arrow) and to a ganglion cell (GC) dendrite (black/white arrow) in S1. The GC dendrite is also postsynaptic to an unstained amacrine cell (A). A neighboring unstained amacrine cell (A) is presynaptic to another Toh-IR process.
b) A vesicle-filled Toh-IR process is presynaptic (black/white arrow) to an unstained amacrine cell (A) in S1 of the IPL.
c) A large Toh-IR process makes a synapse upon another smaller Toh-IR profile in S1.
d) A Toh-IR profile on the S4/5 border synapses upon a colloidal gold-containing GABA-IR (Ga) amacrine profile. Scale bar 0.5 um.